Posted by **Anonymous ** on Monday, February 18, 2013 at 10:52am.

You have 800 feet of fencing to enclose a rectangular plot that borders on a river. If you do not fence the side along the river,find the length and width of the plot that will maximize the area. What is the largest area that can be enclosed?

- College Algebra -
**JJ**, Monday, February 18, 2013 at 11:35am
I know how to do this with calculus, but algebraically it starts the same way.

L + 2W = 800 L = 800 - 2w

A = LW

A= (800-2w)w

A = 800w - 2w^2

Take the derivative: 800 -4w

800 -4w = 0 to find max.

800 = 4w

200 =w

l = 400

- College Algebra -
**Anonymous please help :) **, Monday, February 18, 2013 at 11:43am
Thank you!

- College Algebra -
**Yan**, Thursday, August 14, 2014 at 10:17am
How did it become 800-4w from 2400-2w^2?

## Answer this Question

## Related Questions

- Algebra - You have 600 feet of fencing to enclose a rectangular plot that ...
- Math - Show all work You have 92 feet of fencing to enclose a rectangular plot ...
- Math - You have 192 feet of fencing to enclose a rectangular plot that borders ...
- Math - A farmer with 8000 meters of fencing wants to enclose a rectangular plot ...
- Algebra - Farmer Ed has 9,000 meters of fencing, and wants to enclose a ...
- algebra - Farmer Ed has 9 comma 0009,000 meters of fencing, and wants to ...
- Calculus - 600 feet of fencing to enclose a rectangular plot If I don't fence ...
- Math(HELP!) - A farmer has 120 feet of fencing to enclose a rectangular plot for...
- college Algebra - A rectangular fence is to be built along a river using the ...
- algebra - if you have 88 ft of fencing to enclose a rectangular plot but don't ...

More Related Questions